OBJECTIVE: To evaluate the effectiveness of the California Perinatal Quality Care Collaborative quality-improvement model using a toolkit supplemented by workshops and Web casts in decreasing nosocomial infections in very low birth weight infants.DESIGN: This was a retrospective cohort study of continuous California Perinatal Quality Care Collaborative members' data during the years 2002-2006. The primary dependent variable was nosocomial infection, defined as a late bacterial or coagulase-negative staphylococcal infection diagnosed after the age of 3 days by positive blood/cerebro-spinal fluid culture(s) and clinical criteria. The primary independent variable of interest was voluntary attendance at the toolkit's introductory event, a direct indicator that at least 1 member of an NICU team had been personally exposed to the toolkit's features rather than being only notified of its availability. The intervention's effects were assessed using a multivariable logistic regression model that risk adjusted for selected demographic and clinical factors.RESULTS: During the study period, 7733 eligible very low birth weight infants were born in 27 quality-improvement participant hospitals and 4512 very low birth weight infants were born in 27 non-quality-improvement participant hospitals. For the entire cohort, the rate of nosocomial infection decreased from 16.9% in 2002 to 14.5% in 2006. For infants admitted to NICUs participating in at least 1 quality-improvement event, there was an associated decreased risk of nosocomial infection (odds ratio: 0.81 [95% confidence interval: 0.68-0.96]) compared with those admitted to nonparticipating hospitals.CONCLUSIONS: The structured intervention approach to quality improvement in the NICU setting, using a toolkit along with attendance at a workshop and/or Web cast, is an effective means by which to improve care outcomes.